THIS COMPONENT IS ENTITLED THE IMMUNOMONITORING LABORATORY ABSTRACT Project Summary/Abstract The last two decades have seen an ever-increasing growth in our understanding of the interaction between the immune system and cancer. We now know that natural and therapeutically induced immune responses to cancer can prevent and/or facilitate cancer development/outgrowth and we have learned a great deal about the identity and function of the immune cells and molecules that participate in these functions. In addition, new cancer immunotherapies have shown remarkable capacities to induce durable responses in patients with advanced forms of cancer (such as stage IV melanoma) that are generally resistant to any other types of cancer therapy including chemotherapy, radiation therapy or targeted therapy. These findings have significantly changed the thinking about cancer treatment and there is now nearly universal excitement about using the immune system as an important and effective weapon against cancer. The outstanding basic immunology community at WUSM has made major fundamental contributions to the understanding of the complex interplay that occurs between the immune system and cancer. To facilitate translation of our basic research findings into the cancer immunotherapy arena, support ongoing and new clinical cancer immunotherapy trials and develop novel mechanistic insights into human immune system- cancer interactions, a centralized immune monitoring facility was created with support of the Chancellor, WUSM Dean, Executive Faculty and numerous Department Heads. Today the Immunomonitoring Laboratory (IML) is located in prime new research laboratory space on the 7th floor of the BJC Institute of Health in the center of the Washington University Medical School campus and linked to the SCC and Barnes Hospital. The IML is equipped with state-of-the-art equipment and a highly trained staff to monitor immunologic changes occurring during cancer immunotherapy and relate them to treatment outcomes. In addition, IML provides the means to monitor developing immune responses to new therapies in animal models of cancer treatment; to elucidate novel treatment strategies; or develop unique processes to evaluate treatment outcomes in translational studies. As such, this shared resource provides the infrastructure and expertise to advance cancer immunotherapy outcomes.